assorted subtyping tests

[felixrehren]

c.f. master list #19998
tests for closed issues #2552 #8625 #8915 #11407
and #12814 #16922 #17943 #18892 (#19159 #19413) #18985 #19041

[Edit: misunderstood method overwriting as in #18892, thanks yuyichao for correction, now has a test]

[tkelman]

these should use the new syntax

[yuyichao]

Why should it error? You defined two methods that overrides each other and both of them matches the signature you are calling.

[felixrehren]

@tkelman edit: got it, I think. incoming

[felixrehren]

I don't understand the error message

  LoadError: syntax: 
  ERROR: deprecated syntax "inner constructor D8915(...) around /tmp/julia/share/julia/test/subtype.jl:932".
  Use "D8915{T}(...) where T" instead.

and can't work out from NEWS.md what the new syntax should be :/

[tkelman]

typo?

[yuyichao]

and can't work out from NEWS.md what the new syntax should be :/

Have you tried doing exactly what the deprecation warning says?

[StefanKarpinski]

Have you tried doing exactly what the deprecation warning says?

It's on the second line of the error message in case you missed it (I did on first reading).

[tkelman]

call overloading in this style is deprecated

[felixrehren]

I saw that when I tried this is in 0.5, but couldn't figure out the transformation (and the warning had disappeared in 0.6?). How should this be spelled now?

[yuyichao]

You should follow the deprecation warning on 0.5.

(::Type{T}){T<:A12814,X<:Array}(x::X) = 1

[felixrehren]

Thanks all for the help!
@yuyichao @StefanKarpinski I tried to follow the depreciation warning, but I don't understand it (what inner constructor?), and my attempts to fix it haven't worked. I would be grateful for any further pointers / a fix!

[yuyichao]

(what inner constructor?)

The meaning of inner constructor should be very unambiguous: http:https://docs.julialang.org/en/latest/manual/constructors.html#Inner-Constructor-Methods-1

and my attempts to fix it haven't worked.

What didn't work? The depwarn shouldn't be printed anymore?

[felixrehren]

Writing D8915{T}(a) where T = 1 instead of D8915(a) = 1 didn't work: the depwarn is gone, replaced by

LoadError: syntax: "1" is not a valid function argument name
  while loading /tmp/julia/share/julia/test/subtype.jl, in expression starting on line 935

and

Got an exception of type LoadError outside of a @test
ERROR: LoadError: type UnionAll has no field parameters

on two of the Travis builds.

[yuyichao]

Please check the line number. That's not the same line at all.

https://github.com/JuliaLang/julia/pull/20627/files#diff-4cf37a18308090507d83e9d96dd01692R935 is wrong.

[tkelman]

I don't think that deprecation message is all that obvious, fwiw

[yuyichao]

What would be a more obvious one?

[tkelman]

printing the actual contents of the line/signature that caused the warning instead of a (...) abbreviation of it

[yuyichao]

The abbreviated part is not important since it does not need to be changed at all. It should be ok to print it if it's short but when it's longer it'll make it much harder to spot the actual change that needs to be made.

[tkelman]

it is important if it makes it easier to identify what actually needs changing. right now it's not very clear, like when there are multiple inner constructors

[yuyichao]

What about multiple inner constructors? If none of them have type parameters they need to be changed in exactly the same way and are printed as such in the deprecation warning?

[tkelman]

then you should get the warning once per constructor, otherwise fixing one will only change the line number of the warning (if you're lucky) so you don't get much feedback that you partially fixed it

[yuyichao]

then you should get the warning once per constructor

You do?

julia> struct A{T}
           A() = 1
           A(a) = 2
       end

WARNING: deprecated syntax "inner constructor A(...) around REPL[1]:2".
Use "A{T}(...) where T" instead.

WARNING: deprecated syntax "inner constructor A(...) around REPL[1]:3".
Use "A{T}(...) where T" instead.

[yuyichao]

Just noticed that the inner constructor with type parameters is not printed correctly.

julia> struct C{T}
           C{T2}(a::T2) = T2
       end

WARNING: deprecated syntax "inner constructor C(...) around REPL[3]:2".
Use "C{T}(...) where T" instead.

Should say

WARNING: deprecated syntax "inner constructor C{T2}(...) around REPL[3]:2".
Use "C{T}(...) where {T,T2}" instead.

Though this gets a lot trickier for

struct D{T}
    D{T}(::T) = 1
end

which should probably suggest sth like D{_}(::T) where {_,T} = T.

[felixrehren]

What should the correct version of lines 930 - 935 be?

[yuyichao]

mutable struct D8915{T <: Union{Float32,Float64}}
    D8915{T}(a) where T = 1
    D8915{T}(a::Int) where T = 2
end
@test D8915{Float64}(1) == 2

[tkelman]

preferably with curly braces where {T} for a bit nicer readability

[felixrehren]

Is there a problem with remote exceptions? Not sure what to make of this message in the logs, seems to be a different remote worker that failed in each case

Error in testset subtype:
Error During Test
  Test threw an exception of type RemoteException
  Expression: subtype
  RemoteException(1, CapturedException(CompositeException(Any[CapturedException(ErrorException("Error deserializing a remote exception from worker 8\nRemote(original) exception of type Base.Test.TestSetException\nRemote stacktrace : "), Any[(fini...

[yuyichao]

Yes there are some issues with test result serialization so it doesn't actually show the error.

OTOH, please run the tests locally first before pushing.

[tkelman]

bump, needs rebase

[pabloferz]

Rebased (hope you don't mind)

[tkelman]

likely needs "fixing whatever was broken about the tests" too in addition to just a rebase, so this'll probably fail at the moment

[felixrehren]

Thanks for rebase @pabloferz! ❤️ Fixed tests, builds build. LGTM?

[Keno]

Bump @JeffBezanson

[Keno]

Bump @JeffBezanson are any of these still relevant?